Total and specific serum IgE decreases with age in patients with allergic rhinitis,asthma and insect allergy but not in patients with atopic dermatitis

Concerning allergic diseases, the incidence of allergic symptoms, as well as their severity, seems to decrease with age. The decline of onset of allergic symptoms observed in ageing might result from a decrease of serum total and specific IgE. Atopic disorders are complex diseases that involve interactions among several physiological systems, e.g. skin, lung, mucosae, and the immune system. It was the aim of this study to compare the effects of age on total and specific IgE in patients with atopic dermatitis (AD), allergic rhinitis or asthma, and insect allergy, respectively.     

Antibacterial properties of eosinophil major basic protein and eosinophil cationic protein

We examined the bactericidal activity of two proteins that are abundant in the cytoplasmic granules of human eosinophils, major basic protein (MBP) and eosinophil cationic protein (ECP). Unlike the human neutrophil's peptide defensins, both MBP and ECP killed stationary phase Staphylococcus aureus 502A in a simple nutrient-free buffer solution. Although MBP also killed Escherichia coli ML-35 with considerable efficacy under these experimental conditions, the in vitro activity of ECP against E. coli was considerably enhanced if mid-logarithmic phase bacteria replaced stationary phase organisms or if the assay medium was enriched with trypticase soy broth. The antibacterial activity of both eosinophil proteins was modulated by incubation time, protein concentration, temperature and pH. A pBR322-transformed derivative of E. coli ML-35 was used to examine the effects of ECP and MBP on integrity of the bacterial inner membrane (IM) and outer membrane. Although both MBP and ECP caused outer and inner membrane permeabilization when nutrients were present, only MBP was effective under nutrient-free conditions. Two proton ionophores (DNP and carbonyl cyanide m-chlorophenyl hydrazone) protected E. coli from the bactericidal effects of ECP but not from MBP. These findings establish that MBP and ECP have bactericidal properties and suggest that these proteins kill E. coli by similar but nonidentical mechanisms marked by an attack on the target cell's membranes. In view of evidence that high concentrations of ECP and MBP exist in cytoplasmic granules whose contents are translocated to phagocytic vacuoles, we suggest that MBP and ECP contribute to the eosinophil's ability to kill ingested bacteria.     

Systemic and local eosinophil inflammation during the birch pollen season in allergic patients with predominant rhinitis or asthma

Background

The aim of the study was to investigate inflammation during the birch pollen season in patients with rhinitis or asthma.

Methods

Subjects with birch pollen asthma (n = 7) or rhinitis (n = 9) and controls (n = 5) were studied before and during pollen seasons. Eosinophils (Eos), eosinophil cationic protein (ECP) and human neutrophil lipocalin were analysed.

Results

Allergic asthmatics had a larger decline in FEV1 after inhaling hypertonic saline than patients with rhinitis (median) (-7.0 vs.-0.4%, p = 0.02). The asthmatics had a lower sesonal PEFR than the rhinitis group. The seasonal increase in B-Eos was higher among patients with asthma (+0.17 × 109/L) and rhinitis (+0.27 × 109/L) than among controls (+0.01 × 109/L, p = 0.01). Allergic asthmatics and patients with rhinitis had a larger increase in sputum ECP (+2180 and +310 μg/L) than the controls (-146 μg/L, p = 0.02). No significant differences in inflammatory parameters were found between the two groups of allergic patients.

Conclusion

Patients with allergic asthma and rhinitis have the same degree of eosinophil inflammation. Despite this, only the asthmatic group experienced an impairment in lung function during the pollen season.     

Distinctive cationic proteins of the human eosinophil granule: major basic protein, eosinophil cationic protein, and eosinophil-derived neurotoxin

The human eosinophil granule contains a number of cationic proteins that have been identified and purified to homogeneity, including the major basic protein (MBP), the eosinophil cationic protein (ECP), and the eosinophil-derived neurotoxin (EDN). Because of confusion in the literature regarding the distinctiveness of MBP and ECP, we investigated the immunochemical and physicochemical properties of these purified proteins by electrophoresis on sodium dodecyl sulfate-polyacrylamide gels (SDS-PAGE), by specific double antibody radioimmunoassays (RIA) for MBP and ECP, and by fractionation of acid-solubilized eosinophil granules on Sephadex G-50 columns. Analysis of a mixture of the three purified proteins by SDS-PAGE showed that they migrated as three distinct bands with differing m.w. Comparison by specific RIA for MBP and ECP did not demonstrate any appreciable immunochemical cross-reactivities among the three proteins. Sephadex G-50 column fractions of acid-solubilized eosinophil granules were analyzed by RIA and by SDS-PAGE analysis of individual column fractions. MBP, ECP, and EDN eluted at different volumes from Sephadex G-50 columns as determined by RIA and SDS-PAGE. Soluble extracts of eosinophil granules from patients with the hypereosinophilic syndrome contained between six and 64 times more MBP than ECP on a weight basis. These observations demonstrate that MBP, ECP, and EDN are distinctive cationic proteins of the human eosinophil granule and that eosinophil granules from patients with eosinophilia contain considerably greater quantities of MBP than ECP.     

Localization of eosinophil cationic protein, major basic protein, and eosinophil peroxidase in human eosinophils by immunoelectron microscopic technique

An immunoelectron microscopic technique using protein A-gold as a specific marker was used for precise intracellular localization of eosinophil granule proteins. Eosinophils from healthy individuals were isolated in metrizamide gradients. Eosinophil cationic protein (ECP) and eosinophil peroxidase (EPO) were clearly located in the matrix of the large crystalloid-containing granules. In addition, ECP was probably present in the small granules of eosinophils. Major basic protein (MBP) was present in the crystalloid structure of specific granules. This method can be applied in studies of eosinophil degranulation to trace the release of biological effector molecules.     

Survey on the impact of comorbid allergic rhinitis in patients with asthma

Background

Allergic rhinitis (AR) and asthma are inflammatory conditions of the airways that often occur concomitantly. This global survey was undertaken to understand patient perspectives regarding symptoms, treatments, and the impact on their well-being of comorbid AR and asthma.

Methods

Survey participants were adults with asthma (n = 813) and parents of children with asthma (n = 806) from four countries each in the Asia-Pacific region and Europe. Patients included in the survey also had self-reported, concomitant AR symptoms. Patients and parents were recruited by telephone interview or by direct interview.

Results

Most patients (73%) had pre-existing symptoms of AR when their asthma was first diagnosed. Shortness of breath (21%) was the most troublesome symptom for adults, and wheezing (17%) and coughing (17%) the most troublesome for children. Patients used different medications for treating asthma (most commonly short-acting β-agonists and inhaled corticosteroids) and for treating AR (most commonly oral antihistamines). The concomitant presence of AR and asthma disrupted the ability to get a good night's sleep (79%), to participate in leisure and sports activities (75%), to concentrate at work or school (69% of adults, 73% of children), and to enjoy social activities (57% of adults, 51% of children). Most patients (79%) reported worsening asthma symptoms when AR symptoms flared up. Many (56%) avoided the outdoors during the allergy season because of worsening asthma symptoms. Many (60%) indicated difficulty in effectively treating both conditions, and 72% were concerned about using excessive medication. In general, respondents from the Asia-Pacific region reported more disruption of activities caused by symptoms and more concerns and difficulties with medications than did those from Europe. Differences between the two regions in medication use included more common use of inhaled corticosteroids in Europe and more common use of Chinese herbal remedies in the Asia-Pacific region.

Conclusion

Results of this survey suggest that comorbid asthma and AR substantially impact patient well-being and that the worsening of AR symptoms in patients with asthma can be associated with worsening asthma symptoms. These findings underscore the need for physicians who treat patients with asthma to evaluate treatment options for improving symptoms of both AR and asthma when present concomitantly.

     

Peptides of major basic protein and eosinophil cationic protein activate human mast cells

The eosinophil granule proteins, major basic protein (MBP) and eosinophil cationic protein (ECP), activate mast cells during inflammation; however the mechanism responsible for this activity is poorly understood. We found that some theoretical tryptase-digested fragments of MBP and ECP induced degranulation of human cord blood-derived mast cells (HCMCs). The spectrum of activities of these peptides in HCMCs coincided with intracellular Ca²⁺ mobilization activities in Mas-related G-protein coupled receptor family member X2 (MRGPRX2)-expressing HEK293 cells. Two peptides corresponding to MBP residues 99–110 (MBP (99–110)) and ECP residues 29–45 (ECP (29–45)), respectively, induced degranulation of HCMCs and intracellular Ca²⁺ mobilization in MRGPRX2-expressing HEK293 cells in a concentration-dependent manner. Stimulation with MBP (99–110) or ECP (29–45) induced the production of prostaglandin D2 by HCMCs. The activities of MBP (99–110) and ECP (29–45) in both HCMCs and MRGPRX2-expressing HEK293 cells were inhibited by MRGPRX2-specific antagonists. In conclusion, these results indicated that MBP and ECP fragments activate HCMCs, and it may occur via MRGPRX2. Our findings suggest that tryptase-digested fragments of eosinophil cationic proteins acting via the MRGPRX2 pathway may further our understanding of mast cell/eosinophil communication.     

Arachidonic acid metabolites and their circadian rhythm in patients with allergic bronchial asthma

The aim of this study was to investigate circadian variation in concentrations of arachidonic acid (AA) metabolites in relation to the circadian pattern in bronchial patency. Blood samples were obtained at 4-hr intervals from 2000 of 1 day until 1400 of the next from 12 diurnally active asthmatic and six diurnally active non-asthmatic patients. Bloods were analyzed for the prostanoids thromboxane A2 (measured as stable metabolite 6-keto-PGF1a), PGE2 and PGF2a. Airways patency was assessed by self-measurement of peak expiratory flow (PEF). In asthmatics, circadian variation was detected in PEF as well as PGE2 and TXB2. The circadian trough of the PEF rhythm closely coincided with the circadian peak of the PGE2 and TXB2 rhythms. In the controls, the PEF was not circadian rhythmic. Of the AA metabolites only 6-keto-PGF1a exhibited 24-hr bioperiodicity in the controls. The controls exhibited a significantly higher circadian mean of PEF (P less than 0.001), while the asthmatics had a lower 24-hr average PGE2 but greater mean TXB2/PGE2 ratio. The obstructive effect caused by the overall 24-hr deficiency of PGE2 in asthmatics is possibly amplified by the increased of TXB2 during the early morning hours. This dissociation of the temporal patterns in TXB2 and PGE2 levels over the 24 hr is discussed as a characteristic finding for asthmatics.     

Interaction of eosinophil granule major basic protein with synthetic lipid bilayers: A mechanism for toxicity

Summary Eosinophil granule major basic protein (MBP) is a potent toxin for mammalian cells and helminths, but the mechaism of its toxicity is not known. Here we tested whether MBP toxicity is exerted through its effect on the lipid bilayer of its targets. Liposomes prepared from synthetic phospholipids were used as targets for MBP and their properties examined by fluorescence and circular dichroism (CD) spectroscopy. MBP caused a change in the temperature transition profiles of acidic liposomes (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidyl serine or an equimolar mixture of 1,2-dimyristoyl-sn-glycero-3-phosphocholine and 1,2-dimyristoyl-sn-glycero-3-phosphatidic acid) and induced their aggregation as shown by fluorescence resonance energy transfer experiments. The CD spectra and fluorescence characteristics of MBP itself were altered by its interaction with acidic lipids. Blue shifts in the emission maxima of the Trp, and of the dimethylaminonaphthyl moiety in acrylodan-labeled MBP, and a reduction in the effectiveness of quenching of Trp fluorescence by acrylamide were observed in the presence of acidic lipids. None of these effects were noted with zwitterionic lipids. This MBP : lipid bilayer interaction resulted in fusion and lysis of liposomes as indicated by the fluorescent indicator calcein. The results demonstrate that MBP associates with acidic lipids and that it disrupts, aggregates, fuses, and lyses liposomes prepared from such lipids. Such interaction might account for its wide range of toxicity.Abbreviations used Acrylodan 6-acryloyl-2-dimethylam-inonaphthalene - CD circular dichroism - DMPA 1,2-dimyrist-oyl-sn-glycero-3-phosphatidic acid - DMPC 1,2-dimyristoyl-sn-glycero-3-phosphocholine - DPH 1,6-diphenyl-1,3,5-hexatriene - DTT dithiothreitol - FRET fluorescence resonance energy transfer - HEPES N-2-hydroxyethyl piperazine-N-2-ethane sulfonic acid - K _sv Stern-Volmer constant - K _q bimolecular quenching coefficient - _em emission wavelength - _ex excitation wavelength - MBP major basic protein - MOPC 1-oleoyl-2-hydroxy-sn-glycero-3-phosphocholine - NBD-PE N-(7-nitro-2,1,3-benzo-xadiazol-4-yl)-phosphatidylethanolamine - nMBP native major basic protein - PBS phosphate-buffered saline - POPC 1-palmit-oyl-2-oleoyl-sn-glycero-3-phosphocholine - POPS 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidyl serine - raMBP reduced and alkylated major basic protein - RHO-PE rhodamine-phosphatidylethanolamine - Tes N-tris[hydroxymethyl]-methyl-2-amino-ethane-sulfonic acid - Tris tris[hydroxymethyl]-amino-methane We would like to thank Dr. Predrag J.K. Ilich for assistance with initial data analysis, Dr. Salah S. Sedarous for the lifetime data and for helpful discussions, Dr. S. Yu. Venyaminov for helpful discussions, Mr. Kenneth D. Peters and Mr. Peter J. Callahan for assistance with some of the illustrations, and Ms. Jill Wagner for performing the radioimmunoassays. We would also like to thank Ms. Jill Kappers for excellent secretarial work. This work was supported in part by a Fellowship grant from the American Heart Association, Minnesota Affiliate, and by grants from the National Institutes of Health AI 09728 and from the Mayo Foundation. RIA-G is a Fellow of the American Heart Association.     

Airborne fungal spore distribution in Bangkok,Thailand: correlation with meteorological variables and sensitization in allergic rhinitis patients

Information about airborne fungal spore is crucial for health risk assessment and management, especially for patients with allergy and asthma. Nonetheless, such data are rarely available from certain areas of the world, including Southeast Asia. The aim of this study was to gain updated information about airborne fungal spore in Bangkok, the capital city of Thailand. A survey was conducted at five sampling sites in Bangkok, using the Rotorod Sampler^® for a period of 1 year. High concentrations of spores were found all year with the peak between August and November. The most prominent spore types were Cladosporium, Nigrospora, Puccinia, Aspergillus/Penicillium, and Fusarium. The spore concentrations were positively and significantly correlated with the amount of rainfall and relative humidity, reaching the maximum level in September. Sensitization rates to Cladosporium, Penicillium, and Aspergillus among Thai atopic patients were approximately 16.6, 13.6, and 13.0%, respectively.